Percussion-hammer.



E. L. UPSON & H. W. PLEISTER.

PERCUSSION HAMMER.

4 APPLICATION FILED SEPTLIIL I9l2. 1 163,711. Patented Dec. 14, 1915.

, 3 SHEETS-SHEET I.

T L J I 1/21 LL l/l llnes as: Invenlorz; li'dlmn L. Upsan,

H WP] I By their flttorney j gzy/ e E. L. UPSON & H. W PLEISTER.

PERCUSSION HAMMER.

APPLICATION FILED SEPT. H. I912.

- Patented Dec. 14, 19k).

VVI in 05505: 2 2 In uenlans:

WM Edwin L. 19mm,

Hinrz WP a 510i? Bylhez'r/Zliorney E. L. UPSON & H. W. PLEISTER.

PERCUSSION HAMMER.

APPLICATION FILED SEPT. 11 1912,

1,163.71 1 Patented Dec. 14, 1915.

3 SHEETS-SHEET 3,

5 k \\m 1 H 1 l1 fnvenlons: mfne s'p'es. Edwin L. U ason,

M Henry ll f Pl e ister".

UNITED STATES PATENT OFFICE.

EDWIN L. UPSON, OF BROOKLYN, NEW YORK, AND HENRY W. PLEISTER, OF WEST-FIELD, NEW JERSEY, ASSIGNOBS T6 HENRY B. NEWHALL, OF PLAINFIELD, NEW

JERSEY.

PERCUSSION-HAMMER.

Specification of Letters Patent.

Patented Dec. 14, 1915.

Application filed September 11, 1912. 7 Serial No. 719,735.

of New York, and HENRY 1V. PL n'Is'rnR, a

citizen of the United States, residing at Westfield, in the county ofUnion and State of New Jersey, have invented certain new and usefulImprovements in Percussion- Hammers, of which the following is aspecification.

Our present invention relates to an improvement in percussion hammerswhich may be used for tamping, or cutting holes in hard substances, orfor riveting, or any other use which requires a rapid succession ofblows to perform thenecessary operation.

One of the objects of our improvement is in the construction of thehammer operating device whereby the operator thereof is enabled toperform the required amount of ,work with the minimum amount of musculareffort.

I-leretoforein tools of this type, a great amount of effort was requiredon the part of the-0perator to manually operate the device owing to thegreat amount of spring tension that was placed upon the hammer. Thisspring tension is for the purpose of storing energy and to give thenecessary impact through the hammer to the tool, and in our presentconstruction we have so arranged the -lifting elements of the hammer,that the force necessary to overcome the energy storing means is greatlyreduced.

A further object is the provision of a simple means whereby the operatormay increase or decrease the force of the blow given to the operatingtool being used.

'These objects and other advantageous features will now be described indetail.

i Figure 1 shows the side elevation of our device, with a portion brokenaway to show the interior thereof: Fig. 2 is a front elevation of thesame; Fig. 3 is a diagrammatic view of the device; Fig. 4 is anotherdiagrammatic view showing another position of the operating elements;Fig. 5 is a front elevation of the hammer reciprocating member; Fig. 6is a sectional view of the same taken on the line G( Fig. 5; Fig. 7 isan end view of the hammer. shown in Fig. 8 in side elevation; Fig. 9 isa fragmentary view taken on the line 9-9, Fig. 4, looking in thedirection of the arrow; Fig. 10 is a fragmentary view showing amodification of the device; Fig. 11 is another view of the saidmodification showing certain positions of the relative parts: Fig. 12 isa fragmentary section taken on line 1212 of Fig. 10; Fig. 13 is asectional view of the hammer and .operating member on line 13-13 in Fig.11,

and, Fig. 11 is a sectional view taken on the line 14-41 of Fig. 11.

In Figs. 1 and 2 our device is shown as being comprised of a housingportion 1, and has arranged at the upper end of the said housing a hubor boss 2 which has a threaded socket 3 therein which receives acorrespondinglv threaded stud member 4, which .stud member carries onits, opposite end a rotatable arm or breast plate member 5. Said member5 is rotatably mounted to permit swinging of the tool about its toolaxis during operation. and in one method of mounting it is shown ashaving a depressed seat 6 therein into which the stud 4 projects, andupon the end of which stud is screwed a nut member which retains thesaid breast plate 5 in normal operative position. and at the same timemaintains a spring 3(under tension between the. lower end of the saidbreast plate and the upper portion of the said boss or hub 2. A furtherreason for the above noted construction is that the same afi'ordsa shockabsorber or take-up for vibration during the operation of the tool.

Arranged near the cent r of the tool is a fixed stud 9 which is rigidlvattached t the housing member 1 hr means of threads 10. At the uter endof this stud is rotata ly mounted a hammer aetuating disk member 11which carries upon one of its sides near the peri hery thereof. aplurality of camlike members or pretuberances 12. It is bvious that anvnumber of these cam-like mem ers may be used and we have found inpractice that for the ord nary operating rates of speed. six t nineofthese mem ers are suilicient. as will be disclosed in detail later on.At the lower end of the said house in 1 is arranged another extendingboss 13 which has a tapering c lindrical bore 14 therein. the ore beinglarger at its upper end than at its lower end 15. Immediately below thesaid bore 14 is a threaded socket portion 16 which receives therein alock-nut portion 17 which in turn serves to rigidly hold therein anarbor or chuck piece 18, which chuck piece holds the square shank 19 ofthe tool chuck 20. The tool chuck 20 is arranged after the fashion ofthe ordinary type to hold therein an operating tool 21; in the presentcase a stone cutting tool-known as a rock drill.

In the bore 13 is placed a cylindrical member 22 which is known as thehammer, and the said hammer is so arranged at its upper end that aportion of it is flattened away as at 23, and below the flattenedportion is arran d a cam groove 24, the said cam groove oeing curved,the same developed from a radius or a point 25, as shown in Fig. 2. Thisgroove in Fig. 1 is shown as being deep enoughto receive and permit thepassage therethrough of the cam elements 12 which project from the sideof the actuator member 11, and during the passage of the said members bythe rotation of the said disk in the direction of the arrow 250, Fig. 2,it is obvious that the oncoming portion of one of the cams 12 engagesthe wall of the groove in the hammer 22, and raises the hammer, untilthe said cam has passed through the said groove when the hammer 22immediately drops. The dropping of the said hammer in the present caseis accentuated by an energy-storing means in the form of aheart-shapedspring element 26. which is shown in Fig. 2 as being comprised of a flatspring with an indented portion 27 in the middle the eof which is inengagement with a pin 28. The two ends of said spring member 26 are thencurved downwardly and brought together at a point 29, and are therereceived in a slot 30 which is cut into the upper end of the hammermember 22.

The pin member 28, which engages and holds the spring in operativeposition against the hammer 22, is eccentricallv secured upon a stud 31which is rotatably mo nted in theback wall of the housing 1. Suitablvaffixed to this stud 31 is a handle 32 which is held in operativeconnection to the said stud by any suitable means, in the presentinstance shown as a--nut Upon the housing 1, and-immediately beneath thehandle 32, in radial relation to thesaid stud, 31. is arranged asemi-circular rib 34 which has arran ed on the surface thereof aplurality of depressions 35.

The handle 32 has arranged upon it a corresponding point or detent 36,and the said handle being of thin flexible metal may be withdrawn so asto clezr any of the said holes 35 and upon the rotation of the handleabout thegaxi-s of the stud 31. the pin 28 is caused to shift up anddown therebv increasing or decreasing the amount of tensionon the spring26. and when the desired point is reached the detent 36 is entered am,one of the holes 35, thereby locking the pin 28 agliinst any furthermovement until desir It is natural in hammer construction of this type,where the hammer member 22 is arranged to reciprocate in a bore, that agreat amount of side friction is developed in operating the said hammer,thereby increasing the work that the operator must overcome, especiallywhen this device is operated by means of a hand crank, and to overcomethis difficulty the previously mentioned bore 14 was enlarged at itsupper end and brought down to the normal diameter of the hammer 22 atthe lower end. For the purpose of preventing this tapering bore fromcreating trouble during the operation and to also keep the said plungerin nearly axial alinement with the said bore, we have arranged at theupper end of the said hammer a slot 37, in which is pivotallv attached alink 38. the other end of which is pivotally attached to the casting. asat 39. It is obvious that the up and down motion of the hammer 22 causesthis link to move up and down therewith, the said link constraining thehammer to reciprocate to and fro under the action of the cam members.12, and at the same time to prevent all side thrust against the wall ofthe bore caused by the said actuator. This link and its method ofmounting also acts to prevent the said hammer from rotating in its bore.thereby bloc ing the said cam members 12 and prevcntina the rotation ofthe disk.

It is evident that any means or source of power may be used'to cause therotation of the actuator disk 11. and while anv type of motor mav beused therefor, we have disclosed in the present instance. a crank member40. which is mounted upon the hub of the cam disk 11. the said' cr nkhaving at its opposite end a handle 41 shown in Fig. 1. A second handle42 may be provided at a con enient point on the. opposite side of thecrank or operating side for the purpose of enablin the operator to guidethe said tool du ing its operation.

We have. further pro ided on the lower extending lug 13 a limiting stopA3 which mav be made adiustable so as to he .;f l d or lowered. therebvincreasing or dc'c-" ing the amo'mt of cutting where a rock drill isused. This device. of col rse. rnav be dis pensed with and a steadvingor foot fixture, not shown. he used in its place where the device isused for riveting or u -sc tting.

For the pur ose of more fullv disclosing the device. reference may behad to Figs. 3 and 4 wherein is shown an arrow 44 which indicates thedirection of rotation of the cam disk 11 which carries upononelof itsfaces the cam or lifting members 12.

In Fig. 3 is shown the cam face 120 just entering the hammer groove 24,and the hammer is therebylifted from the shank 19 of the tool carrier,thereby compressing the resilient or springemember 26.

In Fig. 4 the hammer portion is shown as being near the limit of itsupward stroke and the cam face 120 is about to leave the said cam groove21, thereby permitting the hammer to impact sharply upon the upperportion of the tool carrier shank 19 and deivering a heavy blow. One ofthe 1mportant features of this cam action is that owing to the peculiarradial relation of the said cam groove 24, previously referred to, andthe radial position of the operating or lifting faces 121 of the earns12, the two said operating faces remain in constant contact with oneanother throughout their entire length, thereby distributing the wearover a greater surface and increasing the life of the device. Thisfeature of the curving of the said face, is indicated by the radial lineA which is set off a certain distance from, or is tangential to, thecenter B of the said cam disk, and all of the said cam portions 12 aredeveloped from the said relative dimensions, thereby presenting to thehammer groove 24 successively, during one rotation of the disk, apredetermined number of reciprocations and giving the operating tool acertain number of reciprocations per rotation.

Owing to the above noted construction and the ease with which the devicemay be operated, it is possible to operate the cam disk member 11 at amuch greater rate of speed than is usual in devices of this character,with the result that the hammer 22 instead of dropping in its propercycle to be lifted by the next succeeding cam, will deliver its force onthe next succeeding cam member instead of on the shank 19 of the toolholder 20. The force of this blow would then be lost and damage might bedone to the tool, such as for instance, the cams may be battered up orpossibly in some cases broken off entirely, and to obviate thisdifficulty there is shown in Figs. 10 and 11 another type of cam disk111, which is provided with a plurality of teeth 112; these teeth areshown in Fig. 12, which view is a fragmentary section taken on the line12 12, Fig. 10. In all other respects the tool shown in the above notedviews is the same as that shown in Figs. 1, 2, 3, and 4.

For the purpose of preventing the hammer 22, Figs. 10 and 11, fromstriking the teeth 112 instead of being lifted by them, we have changedthe conformation of the cam isk and modified the hammer member 22 insuch a manner that a slightly rounded shouldered projection 144. on thelower part of the hammer groove 24, is also utilized as a cam incombination with said disk 111 so as to return the said hammer in casethe same lags during the operation of the tool. The cam disk instead ofbeing a circular member, as 11 in Figs. 1 and 2, is in the present caseout back from the teeth in such a manner as to leave the straight face45 on the front edge of each oncoming cam. and as indicated at 16 inFig. 11, the face 15 must force the hammer downwardly before the nextoncoming cam engages in the said cam groove to lift. It 'will be seen,therefore,

that the above noted construction wili act as a limiting means to thepossible number of rotations per minute of the said cam disk 111 by theoperator.

Fig. 13 is a fragmentary sectional view of the hammer member 22 showingthe modification of the hammer groove and the said cam 11], and theirmethod of engagement during the operating portion of the stroke,together with the front edge 16 of the said cam portion 112, showing thesaid face 46 in alinement with the hammer groove cam portion -15. Byreferring to Fig. 8, there will be seen a side elevation of the hammer22 which is used in the device disclosed in Figs. 1, 2, 3 and 4, and itwill be noted that the face -17 of the said hammer does not terminate inthe groove as in Fig. 13, but is'cut back far enough from the groove 2-1to give a clearance which is indicated at 48, Figs. 3 and 4. v

Fig. 1-1 is a view taken on line 1414 of Fig. 11, and shows the relativeposition of the cam disk 111 to the hammer 22. It may also be noted thatthe last described cam disk 111 may either be a casting or may be madeof sheet metal stamping of requisite thickness.

Having thus described our claim:

1. The combination in a percussion hammer, of a housing, a groovedreciprocating plunger in said housing. a guide link for said plunger. atension means for said plunger, and a rotatable disk having means forengaging the groove in said plunger to retract the hammer.

2. The combination of a housing. a hammer guided to reciprocate in thehousing. an annular spring connected at diametrically opposite parts tothe hammer and to the casing respectively to move the hammer in onedirection. a rotatable actuator provided with a circular series of camsthereon, the hammer having a shoulder portion engaged by said camssuccessively as the actuator is rotated to thereby raise the hammer andcompress the spring, whereby the hammer is advanced by the spring asreleased from the cams successively,- the connection between the springand the casing comprising a stud rotatable in the casing, a pineccentrically mounted on the stud and engaging the spring, and means forsecuring the stud in different positions to vary the tension of thespring.

3. The combination of a housing, a hammer guided to reciprocate in thehousing. an annu ar spring connected at diametrically invention, we

opposite parts to the hammer arid to the casing respectively to move thehammer in one direction, a rotatable actuator provided with a circularseries of cams thereon, the hammer having a shoulder portion engaged bysaid cams successively as the actuator is rotated to thereby raise thehammer and compress the spring, whereby the hammer is advanced by thespring as released from the cams successively, a second shoulder on theK hammer, and a second series of cams on the actuator arranged to engagesaid second shoulder in alternation with the engagement with the othercams with the first mentioned shoulder. to insure return of the hammerwhen raised by the said first cams.

r. The combination of a housing, a hammer guided to reciprocate in thehousing, an annular spring connected at diametrically opposite parts tothe hammer and to the casing respectively to move the hammer in onedirection. a rotatable actuator provided with a circular series of camsthereon, the hammer having a shoulder portion engaged by said camssuccessively as the actuator is retated to thereby raise the hammer andcompress the spring. whereby the hammer is advanced by the spring asreleased from the cams successively, and a link pivoted to the hammerand extending transversely thereto with its other end pivoted on thecasing and arranged to prevent the hammer from bind iug in its guidewayin the casing.

In a percussion hammer,a housinghaving a tapered guideway. a hammermounted to reciprocate in such guideway, a link pivoted to the rear endof the hammer and to the housing to cause the hammer to slide free ofthe guideway at the rear end of the guideway, a compression memberarranged to advance the hammer when retracted, and a series of rotatablecams intersecting the hammer and arranged to retract the ham mer.

6. The combination of a housing, a hammer guided to reciprocate in thehousing, a spring connected to the hammer and to the casing to move thehammer in one direction,

a rotatable actuator provided with a circular series of cams thereon,the hammer having a shoulder portion engaged by said cams successivelyas the actuator is rotated to thereby raise the hammer and compress thespring, whereby the hammer is advanced by the spring as released fromthe cams successively, the connection between the spring and the casingcomprising a stud rotatable in the casing, a pin eccentrically mountedon the stud and engaging the spring, and means for securing the stud indifferent positions to vary the tension of the spring.

7. A hammer comprising a substantially cylindrical housing provided withan axial mounting for a cam and two diametrically opposed limbs. one ofsaid limbs comprising a hammer socket and the other comprising anabutment. a hammer operable in said socket, extending into said housingand there provided with a cam-engaging shoulder; revoluble on saidmounting a cam disk and thereon a plurality of cams adapted to engage,retract and release said hammer; an adjustable spring strained betweensaid hammer and housing; and operating means connected with said camdisk.

8. A hammer comprising a housing provided with a mounting for a cam andtwo diametrically opposed limbs, one of said limbs comprising a hammersocket and the other comprising an abutment, a hammer operable in saidsocket, extending into said housing and there provided with a convexcam-engaging face inclined to the hammer axis: revoluble on saidmounting a cam disk and thereon a plurality of cams formed with facesconcave and secantto said disk, and corresponding .to and adapted toengage, retract and release said hammer; an adjustable spring strainedbetween said hammer and'housing: and operating means connected with saidcam disk.

EDWIN L. UPSON. HENRY \V. PLEISTER.

Witnesses:

Hnxnr B. NEWIIALL, Jr., ANNA M. WILLIAMS.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents Washington, D. O.

